PORTLAND, Ore. All-star guard Brandon Roy unexpectedly decided to retire because of ongoing knee problems, Greg Oden suffered another medical setback and LaMarcus Aldridge had a minor procedure to treat a heart condition.

Roy issued a statement through the Blazers on Saturday morning. The three-time All-Star said he would seek a determination that he's suffered a career-ending injury to his knees "pursuant to the rules of the collective bargaining agreement."

"My family and health are most important to me and in the end this decision was about them and my quality of life," Roy said.

The Blazers could still use the NBA's new amnesty clause to waive Roy, but as of Friday night, the team was still looking at its options, acting general manager Chad Buchanan said.

Around the league

New Orleans: Coach Monty Williams says uncertainty surrounding Chris Paul and how the Hornets' roster will take shape during free agency has led him to simplify the early practices of training camp.

Paul, who was at the Hornets' practice center on Saturday, has worked with New Orleans for the first two days of training camp. But general manager Dell Demps has acknowledged he already tried to trade Paul to the Los Angeles Lakers and continues to work on deals for the star guard.

Paul is one of only five returning veterans on the squad. Most of the players at Hornets camp are young prospects on non-guaranteed contracts.

Williams says roster uncertainty won't become an excuse and that he expects to win with whichever players end up in New Orleans.

New York: The Knicks have acquired Tyson Chandler from the Dallas Mavericks and sent Ronny Turiaf to the Washington Wizards in a three-team trade.

The Knicks also waived Chauncey Billups and designated him as their amnesty player.

Orlando: Magic spokesman Joel Glass says the team has granted New Jersey, Dallas and the L.A. Lakers permission to talk to Dwight Howard's agent Dan Fegan to discuss possible trades.

Howard denied an ESPN report on Friday after the Magic's first training camp practice that said he met with Nets owner Mikhail Prokhorov and general manager Billy King on Thursday in Miami without the Magic's permission. It followed reports that Howard planned to request a trade to the Nets.

Fegan said in statement that any claims of tampering are false.

Howard is eligible to opt out of his current contract in July 2012.